Rubber composition or compound for the manufacture of paving blocks, slabs, and the like



Sept. 24, 1929. E. DRAULLETTE RUBBER COMPOSITION OR COMPOUND FOR THE MANUFAC 1&4.

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Big I w 4 2 Patented Sept. 24, 1929 PATENT, OFFICE- EDMOND DRAULLETTE, F PARIS, FRANCE RUBBER COMPOSITION OR COMPOUND FOR THE MANUFACTURE OF PAVING- BLOCKS,

' SLABS, AND THE LIKE Original application filed January- 4, 1924, Serial No. 684,446. Divided and this application filed March 5, 1926. Serial No. 92,611. I

This application is a division of application Number 684,446, filed January 4, 1924. Numerous types of rubber paving blocks or slabs are ,already known as well as the methods for manufacturing and laying the same.

Paving blocks or slabs have: already bee formed by using, for the top side, a layer of rubber. of superior quality, and for the under side, a layer constituted by a hardened mixture enclosing a wire gauze and a few cramps and by vulcanizing the whole for shaping blocks which are usually laid on a layer of cement or mortar newly spread upon a concrete bed in which the metallic cramps are driven for holding the paving blocks therein.

Small rubber plates are also formed having, on the under side, dovetail projections, these small rubber plates being usually placed on the wood'paving, which is accordingly grooved for. receiving the dovetail projections, or on a cement bed newly prepared.

Rubber plates are secured, by any adhesive means, on blocks made of wood, brick or other materials.

Blocks the upper layer of which is made of vulcanized rubber, the remainder being composed of a mixture the main ingredient of which is sand have also been proposed.

This mixture comprises, alone or in combination: stones, granite, natural or baked clay, sand, cement, clinker, rock, fibrous or ligneous materials, leather, iron filings, generally speaking any animal vegetal or mineral substance to which is added any kind of rubber, filling materials (organic or inorganic). or residues of petroleum. The whole is mixed with india rubber latex and if necessary with a suitable binding material and finally the mixture is compressed into the shape of blocks which are vulcanized as they are or covered with a layer of rubber.

All these processes and products show after;

experiments concerning wear, that rubber is the bestof thepaving materials used up to this day, but that it presents complications as far as the manufacture is concerned, that the cost price isveryvhigh and that, particularly, nobody hasfound a practical andstrong means for securing the rubber'paving block on the ground covered with concrete.

The most important problem to be actually solved consists therefore in securing the rubber paving block on the foundation in such a manner that the securing means resists to the stresses and pulling strains produced by heavy vehicles running at high speed.

This invention relates to improvements in paving and flagging made of rubber compound and is adapted to avoid or attenuate the above mentioned inconveniences.

It particularly vconsists in compositions or compounds for themanufacture of paving blocks and slabs or flags, compositions or compounds formed of manufactured rubber waste and a mineral mixture, the latter having the property of suitably securing the paving blocks or slabs to the foundation.

The process of manufacture of paving blocks and slabs or flags consists especially in making, by moulding and by vulcanization under pressure, a tile, a brick or a flag, by usinga composition made of natural or artificial rubber or similar products, preferably manufactured-rubber waste, such as air tubes, covers, tyres, mats, etc., mixed in a hot condition with residues resulting from the treatment andpurification of vegetal, animal'or mineral fatty bodies and by incorporating in this composition, by passage between the mixing cylinders, added sulphur and a mineral mixture comprising sand, lime, cement, gravel porphyry, sandstone powder etc., alone or suitably mixed and capable of intimately binding with an intermediate layer of mortar or cement. for securing the block to the foundation, and if necessary becoming united at its upper surface with a layer of composition containing a better quality of rubber.

The said block, being formed in a mould inlayers containing progressively diminishing quantities of the mineral mixture is subsequentlyvulcanized under pressure. It can 9 also, before or after vulcanization, be filled, in its cavities, with mortar or cement, forming an outer bindinglayer, and be applied, fresher dry on the binding bed of the foundation or on bricks or agglomerates for form- 100 ing together paving or flagging blocks ready for use.

The invention is described hereafter in detail with reference to the accompanyingdrawing illustrating, in cross sections,.by

way of example and'diagrammatically, a few 7 formed of a composition made of manufactured rubber waste mixed with sand, lime, cement, gravel, etc.

Figure 3 illustrates the same paving block the cavities of which are filled with mortar or cement.

Figures 4 and 5 show the same paving block filled with mortar or cement forming an outer layer.

Figure 6 illustrates a plate made of manufactured rubber waste and a mineral mixture, this plate being connected by a mortar or a cement, to a brick or an agglomerate, for forming together a paving block.

In the drawing, 1 designates a tile, plate, flag or brick constituted, by moulding and vulcanization under pressure, by a plastic and resilient composition made with manufactured rubber waste and residues of various fatty bodies and in which a mineral mixture has been incorporated at 2.

This composition mainly comprises:

Waste from air tubes, covers, mats and the like, cut up to pieces or rasped 20 to 40% Waste from solid tyres or the like,

cut up to pieces or rasped 65 to 25% The mass is heated to 120 to 150 C. in a mixer for causing the waste to again become plastic through the medium of the residue of the fatty body.

In the paste or pulp thus obtained, is incorporated, by passage between the mixing cylinders, sulphur of supervulcanization and a mineral mixture in the following quantities:

Flowers of sulphur 5 to 15% Plastic body having the above indicated composition 25 to 75% Several mixtures are preferably effected, containing a greater or less quantity of mineral filling material and from these mixtures are made sheets of suitable thickness which are placed. in mould adapted to ,shape the paving block, care being taken to arrange at the bottom which is provided with the cavities and grooves 3and 4, sheets containing the greatest quantity of mineral mixture, preferably formed of large grains, then sheets containing a progressively less quantity of mineral mixture and formed of finer grains and, if necessary, a layer of rubber compound of a better qualitv.

Finally, the filled up mould is placed during 10 to 30 minutes under a press heated to a temperature of 150 to 175 C. and compressing the contents with a pressure of 30 to 75 kilograms per square centimeter.

vAfter the treatment, the blocks are removed from the mould.

In the blocks obtained, the mineral mixture 2 comes to the exterior and forms an adhesive surface which firmly binds 'with the mortar or cement of the intermediate layer serving as a connection between the above described compound plate or paving blockl and the bed of concrete, or the brick or an agglomerate completing the block.

The upper part of the plate 1 can, if nec-" essary, be formed of a layer of composition of a better quality and its surface can be smooth, striated or rough according to the applications and-the result to be obtained.

The lower part of the plate 1 is provided with cavities 3, grooves 4, or with rough ridges for the purpose of increasing the surface through which is effected the binding of the mineral mixture incorporated in the composition and vcoming to the exterior with the mortar or cement of the intermediate layer 5 so as to form gripping'surfaces suflicient for preventing the slipplng of the paving blocks under the stresses and pulling strains of heavy vehicles running at righ speed. I 7

Thus, the rubberized composition with its mineral mixture constitutes an intermediate part which perfectly binds with an upper layer made of rubber or similar material and, on the other hand, through the mineral particles of'the mixture coming to the exterior, forms a sutficient hold with the mortar or cement of the foundation for suitably securing the blocks in position.

These tiles, plates, flags, slabs, bricks, manufactured as above stated can be directly used for road paving, flagging of'pavements, tiling of floors and in various constructions.

In this case, the mortar or cement is applied with a trowel on the lower surface of the plate, so as to fill up the cavities or grooves of the same, either to the level of the surface,

as shown in Fig. 3, or by forming a layer of the plate or paving block-1, and the concrete bed of the foundation. v

The cavities 3 and grooves 4 can also be filled up with mojrtar or cement, or the lower surface may be covered with the latter so as to form a comparatively thin layer 5, as shown in Figs. 3, 4, 5. Thus, after drying, adhesive paving blocks are obtained which it suflices to lay ona fresh layer of mortar or cement, spread over the concrete bed, for suitably securing the said blocks to the foundation.

It is to be understood that blocks composed of the layers 1 and 5 already assembled can be subjected to vulcanization.

Finally, it 1s possible to apply, through the 1 medium of a layer 5 of mortar or cement, the same plates 1 upon bricks or agglomerates 6 so as to form single b1ocks, see Fig. 6, which it suflices to lay on the newly prepared concrete bed for obtaining a good paving.

What I claim as my invention and desire to secure by Letters Patent is:

A composition of matter, comprising Soft rubber waste 20 to 40% Hard rubber waste to 25% Fatty residues 15 to 35% the said composition being prepared by mixing and plasticizing the ingredients at a temperature of C. to C.

In testimony whereof I aflix my signature.

EDMOND DRAULLETTE. 

